Fix building preview I/O arrows being affected by wires

Only check a single layer for potential connection or blockage when
displaying building I/O arrows.

Direct port of tobspr-games#1035.

Co-authored-by: Emerald Block <69981203+EmeraldBlock@users.noreply.github.com>

Author: dengr1065

src/js/game/hud/parts/building_placer.js

@@ -575,12 +575,15 @@ export class HUDBuildingPlacer extends HUDBuildingPlacerLogic {
             let isBlocked = false;
             let isConnected = false;
 
-            // Find all entities which are on that tile
-            const sourceEntities = this.root.map.getLayersContentsMultipleXY(sourceTile.x, sourceTile.y);
+            // Find entity which is on that tile
+            const sourceEntity = this.root.map.getLayerContentXY(
+                sourceTile.x,
+                sourceTile.y,
+                this.fakeEntity.layer
+            );
 
-            // Check for every entity:
-            for (let j = 0; j < sourceEntities.length; ++j) {
-                const sourceEntity = sourceEntities[j];
+            // Check for the entity:
+            if (sourceEntity) {
                 const sourceEjector = sourceEntity.components.ItemEjector;
                 const sourceBeltComp = sourceEntity.components.Belt;
                 const sourceStaticComp = sourceEntity.components.StaticMapEntity;
@@ -633,15 +636,15 @@ export class HUDBuildingPlacer extends HUDBuildingPlacerLogic {
             let isBlocked = false;
             let isConnected = false;
 
-            // Find all entities which are on that tile
-            const destEntities = this.root.map.getLayersContentsMultipleXY(
+            // Find entity which is on that tile
+            const destEntity = this.root.map.getLayerContentXY(
                 ejectorSlotWsTile.x,
-                ejectorSlotWsTile.y
+                ejectorSlotWsTile.y,
+                this.fakeEntity.layer
             );
 
-            // Check for every entity:
-            for (let i = 0; i < destEntities.length; ++i) {
-                const destEntity = destEntities[i];
+            // Check for the entity:
+            if (destEntity) {
                 const destAcceptor = destEntity.components.ItemAcceptor;
                 const destStaticComp = destEntity.components.StaticMapEntity;
                 const destMiner = destEntity.components.Miner;